Post #1176: COVID-19 trend to 7-14-2021

Posted on July 15, 2021


The sporadic nature of most states’ data reporting is adding some variation to the estimate of the trend.  The estimated increase in new cases for the past seven days is only 74% today, not the 92% that came out of yesterday’s calculation.

That said, there have been exactly two instances in this pandemic when the seven-day growth in U.S. new COVID-19 cases exceeded 74%.  Those were the seven-day periods ending yesterday, and the day before yesterday.

Just to say it plainly, for the U.S. as a whole, this rate of growth in new cases is unlike anything we’ve seen so far in the pandemic.

Source for this and other graphs of new case counts:  Calculated from The New York Times. (2021). Coronavirus (Covid-19) Data in the United States. Retrieved 7/15/2021, from”  The NY Times U.S. tracking page may be found at

If you plot the data on a log scale (so that the slope of the line shows the rate of growth), it’s now obvious by eye that this is the sharpest increase in cases that we’ve seen over the course of the pandemic.  Here’s the regional data for the pandemic in natural units, and the same data plotted on a log scale.

The uptick at the end, circled in red, is the current (fifth, Delta) wave of COVID-19 in the U.S.

Three simple points.

First, this isn’t an Act of God, a run of bad luck, or mere random chance.  Back in my June 15 posting, I showed exactly why the numbers were against us on this one.  As I demonstrated in my July 10 posting on this topic, the rapidity of increase for this new COVID-19 wave falls right out of those numbers.  It’s a logical consequence of what we’re doing.  Mix a highly contagious new variant, and a half-vaccinated population, and minimal COVID-19 hygiene, and explosive growth is the rational, expected result.

Second, if behavior doesn’t change, the reasonable expectation is that this growth will continue.  Current conditions are clearly ripe for rapid spread of disease.  If we don’t change the conditions, well, what do you expect to happen?  My guess is, we’re probably going to get rapid spread of disease.  That logic seems pretty clear.

Third, the rate of increase you’re seeing today is due to infections that occurred an average of about 16 days ago.  That’s my best guess for how long it takes the average person to develop symptoms, seek care, get tested, have those tests reported out publicly, and then work into the seven-day moving average.  Factor in that second point above, then right now, the actual in-the-population number of people who were newly infected today should be more than three times the rate shown above.  That’s just last week’s 74% growth rate, compounded.

When I put that all together, I believe the individuals who wanted to let the disease run its course through the population may get their wish.  At the current growth rate, by the time the U.S. CDC and state health departments react to our changed conditions, we’ll be well into the fifth wave.

How should you respond to the fifth U.S. wave of COVID-19?

Source:  The Circumlocution Office.

The question is, what should you — the rational and fully-vaccinated reader — do about this.  If anything.

You’ll see a lot of disinformation, from the usual gang of idiots, to the effect that this variant isn’t dangerous, and so on.  That’s all incorrect.  Presumably anyone bothering to read this knows that.  The raw hospitalization and mortality rates from the current wave reflect the fact that the most vulnerable — the elderly — are largely immunized.  And immunization is extremely effective at preventing hospitalization and death from COVID-19.  Hence, comparing raw case rates across COVID-19 waves doesn’t show you how virulent the virus is.  It’s not an apples-to-apples comparison.

At some point, if I can dig up the data, I’ll have a go at calculating an apples-to-apples comparison between this wave and the prior waves, in terms of  case-rate hospitalization and mortality.  (That’s hospitalizations and deaths divided by the count of formally-diagnosed cases.)   But you have to realize that’s a difficult problem.  The easy part is age-adjusting the rates, so that you’re comparing risk incurred by infected individuals of equivalent ages across waves.  (E.g., how has the risk to an infected 50-year-old man changed between the last wave (Alpha) and those one (Delta).  The hard part is accounting for the effects of immunization itself, among “breakthrough” infections.  Luckily, reported “breakthrough” infections in immunized individuals  remain low enough that I don’t think that will materially affect the results.  , so that you can see that this is not true.  What is true is that most of the elderly have been vaccinated, and that prevents most hospitalizations and deaths.

And of course you see the mainstream media talking about vaccinated individuals who nevertheless got infected.  Particular if there’s some horrific outcome.  But the point is, those stories make the news because they are rare.  Their news value means that they are reported, and so gives the impression that this is an issue far out-of-proportion to the number expected.  That’s not correct.  The actual observed rate of breakthrough infections is less than you would expect in a controlled clinical trial.  That’s presumably due to self-selection.  Individuals smart and/or careful enough to get vaccinated are probably pretty good about avoiding other COVID-19 infection risks.  No vaccines are perfect, but the ones for COVID-19 lower your odds of infection, and particularly our odds of severe infection enormously.

Hospitalization or death aside, the most common severe outcome of COVID-19 infection is the presence “long haul” COVID symptoms.  Although the definition of “long haul” COVID is vague, somewhere around one-quarter of adults experience shortness of breath, fatigue, neurological deficits or other symptoms months after recovery from COVID-19 infection.  As with any measure that includes a wide range of symptoms, it’s not clear how much of that is or is not debilitating.  Fatigue, in particular, is difficult to define or identify with any precision.

We already know that being vaccinated vastly reduces your chances of hospitalization or death from COVID-19 infection.  The last big unknown is whether it reduces the chance of serious long-haul symptoms.  My bet would be “yes”, based in part on a large-scale study conducted by the U.S. Veterans’ Administration (reported here).  But Johns Hopkins says the issue is still undecided, and the U.S. CDC appears to be mute on this issue.

My wife and I are still working through what our response ought to be.  In Virginia, today’s rate of new cases was about 4 per 100,000.  At that rate, being vaccinated, my risk from (e.g.) going to the gym is pretty minimal.  So we haven’t changed that behavior yet.  Otherwise, anywhere there’s no burden in wearing a mask, I am doing so.  And for now, I’m just keeping an eye on things and recalculating the odds of harm as the situation continues to evolve.

To the contrary, as of today, my wife and I are planning the things we’d like to get done before this gets completely out of hand.  If you have something in mind — vacation, say, or similar — might I humbly suggest that you do it sooner rather than later.  In our case, one of our cars died, and we’d really like to replace it.  We’re trying to get that done ASAP, because it surely looks like our risks from being in public indoor spaces are going to go nowhere but up for the near future.

At this point, barring further information, I’m more-or-less of the opinion that this is mostly a problem for the un-vaccinated, and particular those unvaccinated individuals who choose not to implement any COVID-19 hygiene.  At present.

The poster child of the U.S. fifth wave is a maskless, un-vaccinated bar patron.  If individuals have chosen to go that route — no vaccine, no COVID-19 hygiene — then except for my tax dollars supporting their care, and the burden of the inevitable re-imposition of COVID-19 hygiene measures in the sane(r) states, I guess it doesn’t really affect me and mine.  Much.  Yet.

The upshot is that we haven’t changed our routines much, yet.  Instead, we’re hustling to get some things done before the fifth wave picks up more steam.

We are fully aware that the combination of the high growth rate and the roughly 16-day lag between infection and reporting means that we should err on the side of caution.  By the time it’s obvious to most that we ought to resume old COVID-19 hygiene habits, it will be well past the point when we should have done that.  We just have a few bits of business we’d like to see to before that happens.